Tooth and support for same.



F. Z. HANSCOM. TOOTH AND SUPPORT FOR SAME. APPLICATION FILED ocr. 7, 1 910.

1, 174,859. Patented Mar. 7,1916.

55PM 2 3? wwgmm FRANK Z. HANSCOM, OF CHICAGO, ILLINOIS.

TOOTH AND SUPPORT FOR SAME.

Specification of Letters Patent.

' Patented Mar. 7, 1916.

Application filed October 7, 1910. Serial No. 585,749.

' To all whom it may camera:

Be it known that I, FRANK Z. HANsooM, a citizen of the United States, residing at Ghicago,in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Teeth and Supports for Same, of which the following is a specification.

Heretofore it has been common in making artificial teeth to combine facings of porcelain with metallic supporting or base portions, it being the usual practice to make the facing or porcelain part of the tooth as light as possible and the metallic portion relatively strong and bulky. In practice,Ihave found that comparatively light porcelain facings or cutting portions are apt to become easily broken, and furthermore, on account of the large amount of' metal necessary to put into the backing to complete the tooth, the work must be necessarily expensive, as such metal backing is almost entirely made of gold or gold alloy.

One of the objects of the present invention is to provide an artificial tooth in which the porcelain portion is made comparatively large and strong and the metal back or support relatively light, just giving the same sufiicient body to make a firm support for the porcelain portion. I

Another object is to make the tooth and its support of such form that the tooth may be readily slipped into locking position, where it will be held firmly against any force incident to its ordinary use, although it may be readily removed for replacement.

Other objects are to improve the general construction of such artificial teeth, and to provide such advantages as will appear more fully from the following description and the accompanying drawings.

In these drawingsFigure 1 is a side view of a posterior tooth embodying certain features of this invention; Fig. 2 is a sectional view of the tooth support or backing, and shows the method of inserting the tooth; Fig. 3 is a bottom view of the tooth shown in Fig. 1; Fig. 4c is a sectional view taken on the line 4-4 of Fig. 1, and also showing the metallic support in position; Fig. 5 is a side view of a complete tooth and support, showing a modified form of construction used in making a crown.

According to my in 'enticn I prefer to form the porcelain tooth as nearly the size of the natural tooth as is convenient, so as to leave comparatively little space between the cutting or grinding portion of the tooth and the gum. I also prefer to form the metallic sockets or backings as nearly as possible in regular sizes, so that they may be formed up or manufactured separately from the teeth, the arrangement being such that the teeth are provided with engaging portions which will engage securely with the metallic backing or support to form a rigid connection. It will be noted that on account of this method-of construction and arrangement of parts, the strength of the supporting means or metallic backing may be predetermined and thereby avoid the necessity of making the same unduly heavy or strong and avoid the uncertainty incident to the old methods in which each individual backing was formed up around the porcelain portion of the tooth. Furthermore, on ac count of my invention cheaper construction and better effects are secured.

As shown in Fig. 1, the tooth 6, which is preferably made of porcelain or other suitable material, is provided with a curved base 7, which base may be of any desired curvature but is preferably made with its lower surface circular in outline in order'to permit close engagement with the supporting means. The sides 8 of this base portion are preferably slightly undercut as indicated, and these sides, in one form of construction, are continued around on the labial portion of the tooth, as indicated at 9, so as to form, as it were, a continuous undercut shoulder. The undercut or shouldered portion 8 preferably widens toward the occluso-lingual angle of the tooth and stops at a point somewhat below the occlusal surface, as indicated at 10. The metal backing or support 11 consists of a relatively thin plate 12 conforming with the surface of the curved portion 7 of the tooth and having an upwardly extending flange 13 which is undercut to engage with the undercut sides 8, this metallic portion preferably terminating slightly below the occlusal surface of the tooth, although the upper portion engages well around the sides so as to give a firm lateral support. These metallic holders or supporting members may be connected together by solcleringin the usual manner and may be used in connection with bridgework or any of the other well known forms of dental construction. It will be noted that these metallic backings may be stamped or otherwise formed in any number of'the'regular standard sizes, and various forms'ofporcelaln grinding members'may be made to engage with these different sizes, and if desired, such porcelain portions may be readily ground on the occlusal surface to fit differ V cm conditions, without varying the base portion which engages with the metallic support.

' On account of the supports or backings being made in the form shown, when it is desired to secure a tooth in position, all that is necessary is to press the tooth in as indicated in Fig. 2 until it fits firmly within the socket formed therefor, and on account of the peculiar form of this socket or backing,

it will hold the tooth firmly against all of the ordinary strains to which it is subjected when in use. Any suitableadhesive mate rial or cement may be used for assisting in holding the tooth in position. Furthermore, by curving the engaging portion of the tooth from the occluso-lingual angle of the tooth toward the gum as indicated, this gives a large substantial form of tooth, which tends to fill inthe space in asimilarrman'ner to the natural teeth. In some instances, 1 may provide the plate 12 with an inwardly protance from the outer or bucco-cervical angle of the tooth, so that little or no metal can be seen from this side of the tooth. On ac countof these side members converging as indicated in Fig. 3, they will necessarily engage closely with the tooth when it is Copies of thispatent' may be'obtain'ed f'or'five cents each, by: addressing the Commi sion ri Patents,

pressed into position. This form is well adapted for crowning cuspid or bicuspid roots, as showninthisfigure. In this case the metallic holder is secured by soldering or otherwise to a coping 17 secured to the root 18 in the usual manner.

It will be'noted that this particular form of tooth-and support is especially adapted for posterior teeth, although I do not wish to limit myself to this use alone, but 7 What I claim and desire to secure by Letters Patent is:

1. The combination of a tooth having a .convex curve substantially fromthe grinding surface to the gum surface and with undercut grooves, with a concave back or entering said support grooves.

havmg flanges having a. groove extending substantially around said engaging portion, 1 I

2. A tooth of porcelain or the like, havring a convex engaging portion opposedto the occluso-buccal angle of the tooth and 3.1 The, combination of a tooth havi-ng a curved engaging portion with undercut sides and having a lateralgroove therein adjacent to the occlusal surface of .the tooth,

and a metallic back curved to correspond withsaid engaging portion and having undercut flanges, and an inwardly extending projection on saidback adapted to engage with the groove in said toot 4. A tooth having an inclined and conveXly curved base, a back inclined and curved to fit the base and a flange extending around the bottom and two sides of the tooth leaving the fourth upper side open for the- Washington, D. G. 

